ARM announces Ares

none (none.delete@this.none.com) on February 21, 2019 2:59 am wrote:
> Michael S (already5chosen.delete@this.yahoo.com) on February 21, 2019 12:47 am wrote:
> > none (none.delete@this.none.com) on February 20, 2019 11:03 pm wrote:
> > >
> > > I hope they won't do as Intel that still don't have AVX on all of their CPU more than
> > > 10 years after it was announced.
> > >
> >
> > You mean, you have hopes that by 2026 all ARMv8-A cores shipped in new silicon
> > will include support for SVE? Given Arm's business model, the chance for it
> > appears very close to zero. Personally, I don't consider it a problem.
>
> What in ARM's business model would prevent from having SVE in v8A cores according to you?
>
> A 128-bit SVE should not be significantly larger than Neon and could reuse the datapaths,
> so it'd be better to have it even on lower end A class CPU.
>
> > The problem right now is not that SVE support is not universal, but that it does
> > not exist at all, even in cores like N1, where it would already make sense.
>
> Agreed. But that's not what I had in mind. Once ARM has a core with SVE, I would prefer
> that they have it in every A class CPU, contrary to what Intel does. ARM already made a
> mistake by making Neon optional on Cortex-A9, which resulted in NVidia not using it, which
> in turn meant that Android did not have support for Neon enabled by default in their
> toolchains for years, and you had to have two codepaths.

Agree with that, I think even a 128 bit version would simplify a lot of things and be a performance boost. The problem I can see is that it would require everybody to implement it and it would need to be free to any ARMv8 licencee. I don't think there would be an appreciable area cost and the design cost would be fairly reasonable I believe if they don't need to optimise things like scatter gather.